【作者】 龚红红；

【导师】 柳明珠；

【作者基本信息】 兰州大学 ， 高分子化学与物理， 2012， 硕士

【摘要】 自活性染料问世以来,国内外一直主要沿用海藻酸钠(SA)作为活性染料印花糊料增稠剂,因为海藻酸钠具有易着色、得色量高、色泽鲜艳及印花后织物手感柔软等特点。近年来,随着印花技术的不断发展,对印花色浆特别是印花糊料增稠剂提出了更高的要求,仅使用海藻酸钠已远远不能满足高质量印花的要求。另外,由于海藻酸钠资源紧张,价格日趋上涨,使印花成本不断提高,直接影响到生产厂家的经济效益。因此,寻找海藻酸钠的理想替代品不但可以改善印花性能,而且可以降低生产成本。本论文以瓜尔胶为原料,采用干法对其进行氧化和羧甲基化改性,研究改性后的产物与多种天然聚多糖的复配性能,并对复配以后的混合糊料用于活性印花及印花后的各项性能进行了初步探讨。具体包括以下几方面的内容：(1)用双氧水作氧化剂,采用干法对瓜尔胶进行氧化改性,制备了氧化瓜尔胶(OGG)。为了得到一种适合活性印花的产品,考察了各反应条件如氧化剂用量、溶剂用量、反应温度、反应时间对产物粘度的影响,得到制备OGG的最优条件为：氧化剂用量7%,溶剂用量30%,反应温度65℃,反应时间1h；通过傅里叶变换红外(FTIR)分光光度计、凝胶渗透色谱(GPC)、扫描电子显微镜(SEM)及示差扫描量热仪(DSC)对产物进行了表征；测定了原胶及OGG的水合速率,研究了OGG水溶液在不同条件下的流变性能,考察了盐浓度及pH值对产物水溶液粘度的影响；将改性后的产物用于活性印花,从印花后织物纤维硬度、得色及边缘清晰度等方面进行了考察,结果表明,OGG可以用作活性染料印花糊料增稠剂。(2)采用干法对瓜尔胶进行羧甲基化改性,优化了反应条件,得到制备高取代度羧甲基瓜尔胶(CMGG)的最优条件为：氢氧化钠与一氯乙酸的摩尔比为0.55,95%乙醇的体积为15mL,一次反应与二次反应的温度分别为30℃和60℃,一次反应和二次反应的时间分别为40min和10h；通过FTIR, SEM、X射线衍射仪(XRD)及DSC等测试手段对产物进行了表征；研究了CMGG水溶液在不同条件下的流变性能,从CMGG水溶液的粘度测定可以看出,CMGG水溶液是一种非牛顿型流体,存在剪切变稀的假塑性行为,溶液粘度随着浓度的升高而增加,随着温度的升高而降低,随着储存时间的增加先升高后下降；将改性后的产物用于活性印花,结果表明,CMGG作为活性印花增稠剂与SA作为活性印花增稠剂相比,除了得色不如SA深之外,色浆的渗透性及印花后织物的手感均与SA相当,这说明在一定的条件下CMGG可以作为SA的替代品用于活性印花。(3)采用小型实验室平网印花机对OGG和CMGG与SA、羧甲基淀粉(CMS)、羧甲基纤维素(CMC)、黄原胶(XG)的二元和三元复配糊料用于活性印花进行了初步研究。从复配糊料的粘度数据可以看出：无论是二元还是三元复配,各高分子之间均有较强的协同增稠作用,可显著提高混合糊料的粘度。在印染行业中通常用印花粘度指数(PVI)来评估印花色浆的流变性。从色浆的流变性可以看出：SA的加入能显著提高色浆的PVI,使其流变性更适用于活性印花；CMC的加入对混合糊的PVI值影响不大；而CMS和XG的加入只能使混合糊的PVI值降低,这也是CMS和XG用于活性印花的不足之处。印花实验结果表明：与OGG相比,CMGG与SA复配的混合糊所印制织物的手感较软、得色较好,说明CMGG比OGG更适宜用于活性印花；CMGG与CMS复配的印花结果说明在要求不是特别高的情况下,该混合糊可以部分取代SA糊,降低生产成本；从三元复配的印花结果可知,CMC能部分替代SA,降低成本,而XG的加入使得色浆出现胶凝现象,色浆的流动性变差,在印花过程中色浆不能顺利地流下,因此不宜用于活性印花。更多还原

【Abstract】 At present, sodium alginate (SA) is most widely used as a thickener in reactive printing for its easy colored, high quality of color, bright in color and soft handle of fabric after printing. In recent years, with the continuous development of printing technology, it raises high request about printing paste especially printing paste thickener. It doesn’t meet the requirements of high quality printing that only use the sodium alginate as printing paste thickener. Moreover, the fluctuation in price and quality, as well as the limited supply of alginates, has increased the printing cost and affected the manufacturer’s economic benefit directly. Therefore, it is very important to look for the alternatives of sodium alginate, which will not only improve the printing performance but also reduce the production cost. The aim of this thesis was to prepare oxidized guar gum and carboxymethyl guar gum with a simple dry method with guar gum as raw material, study the compatible behavior of modified product and the other natural polysaccharides and study the printing proprieties of all kinds of mixed paste. The main contents were summarized as follows:(1) The aim of this part of the work was to prepare oxidized guar gum (OGG) with a simple dry method and use hydrogen peroxide as oxidant. To obtain a product with suitable viscosity for reactive dye printing, the effects of various factors such as the amount of oxidant and solvent, reaction temperature and time were studied with respect to the viscosity of reaction products. The optimized reaction conditions in the oxidation reaction are:usage of H2O2,7%; percentage of solvent,30%; reaction temperature,65℃; and reaction time,1h. The product was characterized by FTIR, GPC, SEM and DSC. The hydrated rate of guar gum and oxidized guar gum was estimated. The rheological properties of OGG pastes were studied using a rotational viscometer. The effects of the salt concentration and pH on viscosity of the resultant product were studied. In addition, the applied effect of OGG paste in reactive dye printing was examined by assessing the fabric stiffness, color yield and sharp edge to the printed image in comparison with sodium alginate. And the results indicated that the OGG paste could use as thickener in reactive dye printing.(2) Carboxymethyl guar gum (CMGG) was synthesized with a simple dry method. The influences of a variety of reaction parameters for degree of substitution were evaluated. All these are with a view to optimizing the synthesis conditions for high degree of substitution. The optimized reaction conditions in the reaction are: nMCA/nNaOH,0.55; the volume of95%ethanol,15mL; the reaction temperature of the first and second step,30and60℃; and reaction time of the first and second step,40min and10h. The product was characterized by FTIR, SEM, XRD and DSC. The rheological properties of product pastes were studied using a rotational viscometer. The viscosity of products’solution decreased with increasing temperature and increased with increasing concentration. With the increase of storage time, the viscosity increased at first, and then decreased. In addition, a shear thinning pseudoplastic behavior was observed at all concentrations, temperatures and storage times. In addition, the applied effect of CMGG paste in reactive dye printing was examined by assessing the fabric stiffness, color yield and sharp edge to the printed image in comparison with sodium alginate. And the results indicated that the CMGG paste had a good performance as thickener in reactive dye printing.(3) The mixed paste among OGG, CMGG, SA, CMS, CMC and XG was prepared and their viscosities were determined by the viscometer. It can be seen from the viscosity of mixed paste that there existed strong synergistic interactions among the different polysaccharides. The rheological property of the mixed paste was appraised by the printing viscosity index (PVI). From the value of PVI, it can be seen that SA and CMC had a high PVI, but CMS and XG had a low PVI. In addition, the applied effect of mixed paste in reactive dye printing was examined by assessing the fabric stiffness, color yield and sharp edge to the printed image in comparison with sodium alginate. And the results indicated that CMGG had a better applied effect compared with OGG. The mixed paste of CMGG and CMS could partially replace sodium alginate as thickener in reactive dye printing in some situations. In addition, CMC could use as thickener in reactive dye printing but XG couldn’t because of its worse flowability in the process of printing.更多还原